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Test-Retest Reliability of Movement Displacement during a 20-s Stepping-in-Place Test in Community-Dwelling Older Adults with and without Supportive Care
No full textAbstract
Introduction: Our recent reports have shown that movement pattern and displacement assessed with an infrared depth sensor during a 20-s stepping-in-place test (ST) correlates with measures of balance and need for assistance in older individuals. This study investigated ST test-retest reliability in community-dwelling older adults with and without supportive care.
Methods: Two groups were included: those not participating (HO: n = 25, 74.7 ± 5.2 years) and those participating (DSU: n = 41, 78.8 ± 5.8 years) in regular senior day services (supportive care). HO completed three ST trials, separated by 1 week, while DSU completed two ST trials during the same half-day supportive care visit. Testing was conducted with eyes open. ST measures included head movement path distance (TMD), maximum movement displacement (MMD), knee movement path length (KMD), and stepping rate (STEP). TMD×KMD-1 ratio indicated upper-body sway relative to lower-body. Test-retest reliability (intra-class correlation coefficients, ICCs) and between-trial and between group differences (ANCOVA, adjusting for age) were assessed.
Results: After adjusting for age, TMD, KMD, TMD×KMD-1 were lesser and STEP was greater in HO than DUS. HO ST variables did not differ across testing days. HO ICC (1, 3) for TMD (0.911 [95% confidence interval: 0.827-0.958]), MMD (0.918 [0.814-0.961]), KMD (0.838 [0.685-0.923]), and TMD×KMD-1 (0.940 [0.884-0.872]) showed strong to very strong reliability. Similarly, DSU ST variables did not differ across same day trials and ICC (1, 2) for TMD, KMD, and TMD×KMD-1 displayed very strong reliability.
Conclusion: These ST variables exhibited excellent test-retest reliability of discriminating between community-dwelling older adults with and without supportive care
The velar chord and dynamic integration of the gular valve in crocodylians
No full textCrocodylians evolved a unique gular valve that is capable of creating a water-tight seal between the oral and pharyngeal cavities, allowing the animal to safely submerge with an open mouth. The gular valve has traditionally been described as consisting of two separate parts: an active mobile ventral portion (consisting of the tongue and portions of the hyolingual apparatus) and a dorsal portion, which is a static fold on the hard palate (often termed the palatal velum). The results of the present study argue that the two portions of the gular valve are functionally integrated, not separate, and that the dorsal portion (herein the dorsal gular fold) is a dynamic element the shape and tension of which are influenced by active and passive forces. Using gross dissection, histology, and DiceCT, the present study documents a previously underscribed component of the gular valve, the velar chord, which links the hyolingual apparatus to the dorsal gular fold, functionally integrating the two halves of the gular valve. Through endoscopic videography and a variety of manipulations on living crocodylians, this study demonstrates that changes in the tension on the velar chord directly alter the shape and tension of the dorsal gular fold. The shape changes observed in the dorsal gular fold could be accommodated by a shallow depression in the ventral surface of the palatine bones, herein termed the velar fossa. The velar fossa is a prominent feature of Alligator mississippiensis and was observed in other crocodilians; however, a survey of living and fossil crocodylians demonstrated that the velar fossa is not a universal feature in this clade. Understanding the functional linkage between the dorsal and ventral portions of the gular valve has implications beyond the dive reflex of crocodylians, since active manipulation of the dorsal gular fold likely plays a role in a variety of behavioral and physiological processes such as deglutition and vocalization
Total arch extrusion with skeletal anchorage to improve inadequate maxillary incisor display in a case of vertical maxillary deficiency
No full textInadequate maxillary incisor display can negatively impact facial esthetics. Various treatment options exist depending on the underlying cause and severity of the condition. Skeletal anchorage was used to extrude the maxillary dentition and rotate the mandible backward, enhancing visibility of the maxillary incisors. An extrusion assembly was introduced to achieve orthodontic extrusion. Use of bite raisers and interarch elastics was also discussed. Treatment results demonstrated successful achievement of the treatment goals. In addition to optimal occlusion, the patient’s facial profile improved with increased lip fullness. There was an increase in vertical facial height, and maxillary incisor display was significantly improved, resulting in a more pleasant smile. Two-year postretention records evidenced the stability of total arch extrusion to improve maxillary incisor display
Influence of occlusal thickness on the fracture resistance of chairside milled lithium disilicate posterior full-coverage single-unit prostheses containing virgilite: A comparative in vitro study
No full textPurpose: To evaluate the fracture resistance of chairside computer-aided design and computer-aided manufacturing (CAD-CAM) lithium disilicate mandibular posterior crowns with virgilite of different occlusal thicknesses and compare them to traditional lithium disilicate crowns. Materials and Methods: Seventy-five chairside CAD-CAM crowns were fabricated for mandibular right first molars, 60 from novel lithium disilicate with virgilite (CEREC Tessera, Dentsply Sirona), and 15 from traditional lithium disilicate (e.max CAD, Ivoclar Vivadent). These crowns were distributed across five groups based on occlusal thickness and material: Group 1 featured CEREC Tessera crowns with 0.8 mm thickness, Group 2 had 1.0 mm thickness, Group 3 had 1.2 mm thickness, Group 4 with 1.5 mm thickness, and Group 5 included e.max CAD crowns with 1.0 mm thickness. These crowns were luted onto 3D-printed resin dies using Multilink Automix resin cement (Ivoclar Vivadent). Subsequently, they underwent cyclic loading (2,000,000 cycles at 1 Hz with a 275 N force) and loading until fracture. Scanning electron microscopy (SEM) assessed the fractured specimens. Statistical analysis involved one-way ANOVA and the Kruskal-Wallis Test (α = 0.05). Results: Fracture resistance varied significantly (\u3c0.001) across mandibular molar crowns fabricated from chairside CAD-CAM lithium disilicate containing virgilite, particularly between crowns with 0.8 mm and those with 1.2 and 1.5 mm occlusal thickness. However, no significant differences were found when comparing crowns with 1, 1.2, and 1.5 mm thicknesses. CEREC Tessera crowns with 1.5 mm thickness exhibited the highest resistance (2119 N/mm2), followed by those with 1.2 mm (1982 N/mm2), 1.0 mm (1763 N/mm2), and 0.8 mm (1144 N/mm2) thickness, whereas e.max CAD crowns with 1.0 mm occlusal thickness displayed the lowest resistance (814 N/mm2). Conclusions: The relationship between thickness and fracture resistance in the virgilite lithium disilicate full-coverage crowns was directly proportional, indicating that increased thickness corresponded to higher fracture resistance. No significant differences were noted among crowns with thicknesses ranging from 1 to 1.5 mm. This novel ceramic exhibited superior fracture resistance compared to traditional lithium disilicate
Evaluation of nasal septum deviation via reformatted computed tomography (CT) imaging following expansion using RPE and MARPE
No full textObjective: To evaluate whether rapid palatal expansion (RPE) or miniscrew-assisted rapid palatal expansion (MARPE) affects nasal septum deviation (NSD). Materials and Methods: The study population includes 22 RPE patients ages 9.62 ± 1.38 years and 20 MARPE patients ages 19.38 ± 7.82 years with initial diagnostic cone-beam computed tomography (CBCT) scans (T0). Another CBCT scan (T1) was taken after patients underwent RPE or MARPE expansion treatment alone. NSD was evaluated three-dimensionally using a custom landmark analysis on T0 and T1 CBCT scans. Principal component analysis (PCA) and canonical variate analysis (CVA) were used to identify nasal septum shape differences before and after expansion treatment. Results: PCA and CVA showed that while there was change in nasal septum shape from T0 to T1 for MARPE and RPE treatments, the general pattern in morphological change was not found when comparing the variety of phenotypes between individuals. The Procrustes ANOVA regression found P-values for MARPE centroid size and shape were 0.7861 and 1, and RPE centroid size and shape were 0.3508 and 1, respectively, suggesting that there were no significant differences in nasal septum size and shape following expansion. CVA found P-values were 0.99 for MARPE and 0.99 for RPE after 10,000 permutation tests for Procrustes distances, indicating that there were no significant differences between T0 and T1 group means for both treatment groups. Conclusions: MARPE and RPE expansion treatments had no effect on nasal septum deviation from T0 to T1
Creative biomechanics for complex cases
No full textOrthodontic biomechanics play a crucial role in achieving successful outcomes, especially in complex cases requiring precise control of tooth movements. This article explores force system analysis based on the moments and forces around the center of resistance and emphasizes traditional and contemporary approaches in orthodontic biomechanics, focusing on key tooth movements such as bite opening, space closure, retraction, protraction, intrusion, and extrusion. In complex borderline cases involving nonsurgical treatment, this article addresses the significance of total arch distalization for maximum retraction, total arch intrusion for vertical control, total arch extrusion for enhancing maxillary incisor display, lever arm mechanics for achieving incisor torque control, and total arch protraction for improving the maxillary incisor show. Patient-specific factors, efficient biomechanics, and a comprehensive understanding of the limitations of treatment modalities are emphasized in pursuit of optimal orthodontic outcomes
Anterior open bite correction via molar intrusion: Diagnosis, advantages, and complications
No full textABSTRACT Anterior open bite can be effectively treated nonsurgically via molar intrusion. This technique, involving the intrusion of posterior teeth using temporary skeletal anchorage devices, prompts counterclockwise rotation of the mandible. This rotation not only corrects anterior open bite but also contributes to a decrease in anterior facial height, improvements in lip incompetency, and forward movement of the chin. For successful outcomes, temporary skeletal anchorage devices, installed on both the buccal and palatal sides, must deliver equivalent intrusion force to the maxillary teeth. Treatment planning should consider factors such as skeletal discrepancies, vertical excess, incisor exposure, and configuration of the occlusal plane. Clinicians are advised to closely monitor periodontal changes and consider overcorrection to ensure lasting stability and maintenance of incisal overlap post-treatment
Precautions and possibilities in orthodontic treatment of periodontally compromised patients: Current recommendations
No full textAbstract Objective
Orthodontic treatment plays a crucial role in achieving optimal dental esthetics and functional occlusion. However, when periodontally compromised patients are involved, additional precautions and considerations are critical. This article aims to provide up-to-date recommendations for the orthodontic treatment of periodontally compromised patients. Clinical Considerations
Comprehensive diagnosis of the patient\u27s periodontal status, inherent malocclusion, and secondary malocclusion resulting from periodontal disease are essential for achieving optimal esthetics and functional occlusion. This can be facilitated through the use of a simplified checklist. Prior to orthodontic treatment, pre-existing periodontal diseases should be managed. Light and controlled forces should be used to minimize the risk of adverse effects on the periodontium, and any potential traumatic occlusion during tooth movement should be minimized. Furthermore, careful anchorage management is required, and proper application of temporary anchorage devices can significantly expand the scope of orthodontic treatment. Finally, treatment results are maintained by ongoing supportive periodontal therapy even during the retention period. Conclusions
This article presents clinical cases demonstrating the importance of accurate diagnosis in orthodontics and periodontics and the positive impact of orthodontic treatment on patients with pre-existing periodontal diseases. Clinical Significance
An up-to-date orthodontic treatment protocol for periodontally compromised patients is presented